It may not be the most seductively named item in the fashion firmament, but at £17, at least the “johnny hat” — so called because its loose, domed crown resembles a condom — is one of the more affordable fashion trends of recent months.

It is also one of the most ubiquitous. Women have long embraced the cosiness of a beanie hat. More surprising is their popularity among men this winter. Fans include Harry Styles, Brad Pitt, Jude Law, Lenny Kravitz, Bill Murray and Usain Bolt. While Marks & Spencer has reported a 50 per cent rise in men’s beanies compared with